Chromosome 3 is 7% of the human genome and encompasses 230 megabases of DNA. Despite its size, chromosome 3 has been slow to accumulate markers. Recently, a large number of new markers have been generated for chromosome 3, as evidenced by the large number of DNA segments assigned to chromosome 3: there has been an increase from 100 markers to 1600 over the past 3 years. Consequently, now we will be able to begin to construct maps for chromosome 3. The purpose of this workshop is to consolidate data from many labs to construct physical, linkage and radiation maps for chromosome 3. These maps will establish the common bases for the maps, identify overlap, identify areas that need resolution, and set up a resource for common reagents. The workshop will be two days in march, 1992 at the Eisai Convention Room, Bunkyo-ku, Tokyo, Japan. The structure of the meeting will be a series of short presentations by each of the laboratories involved followed by an intense working session to resolve inconsistencies in the map and to produce consensus maps. Relevant material generated at this meeting will be presented in a published report.